Directional antenna array



Feb. 24, 1959 D. 1.. HINGS DIRECTIONAL ANTENNA ARRAY 4 Sheets-Sheet 1 Filed April 10, 1953 FRONT FIGJ REAR

4. 2 I. f l 2% INVENTOR. DONALD L. H/NGS F!G. IO

v BY

Feb. 24, 1959 D. L. HINGS 2,875,433

DIRECTIONAL; ANTENNA ARRAY Filed April-l0, 1953 4 Sheets-Sheet 2 INVENTOR. DONALD L. HINGS L BY r mm WM M 1 Feb. 24, 1959 Filed April 10, 1953 D. L. HINGS DIRECTIONAL ANTENNA ARRAY 4 Sheets-Sheet 3 FIG? INVENTOR. I DONALD L. H/NGS Feb. 24, 1959 D. L. HINGS DIRECTIONAL ANTENNA ARRAY 4 Sheets-Sheet 4 Filed April 10, 1953 INVENTORZ DONALD L. HINGS United States Patent DIRECTIONAL ANTENNA ARRAY Donald L. Hings, Vancouver, British Columbia, Canada Application April 10, 1953, Serial No. 347,872 20 Claims. (Cl. 343-733) This invention relates in general to directional antenna arrays and more particularly to antennas such as V. H. F. antennas which utilize a plurality of elements to obtain a highly directive pattern in the horizontal plane for a high gain.

At V. H. F. frequencies the element lengths of antennas are of practical length for self-support. Using the Yagi principle of a reflector and a plurality of tapered directors, the direetivity of a one-half wave dipole can be increased. With the Yagi principle, in order to obtain maximum gain, fiveor eight directors have been used; and the broader the spacing between the directors, the greater the forward gain of the antenna array. In television work a broad band width is required; and with a multi-element Yagi array, the maximum gain achieved by using more directors is oifset by the narrower band width obtained. Still further, the director elements are parasitic elements and the effect of adding additional directors continually decreases. With a ten-element Yagi array spaced apart at optimum spacing, the entire array becomes quite long and cumbersome.

An object of the invention is to provide an antenna array having many elements in a short length.

Another object of the invention is to provide an additional antenna array having a high gain consistent with a wide frequency band width.

Another object of the invention is to provide an antenna array which may be used with horizontally polarized radio waves and which is mounted on a horizontal boom of only one-half wave length.

Another object of the invention is to provide an antenna having a high gain in the forward direction and a relatively high front-to-back ratio.

Another object of the invention is to provide a series of crossed antenna elements which are effectively coupled together to obtain radiation from each element rather than using them as parasitic elements.

Still another object of the invention is to provide crossed antenna elements which are crossed in the plane of the radio wave and which are coupled together near the crossing point in such a manner that current coupling exists which is in phase to reinforce the signal strength and hence increase the gain and directivity of the antenna array.

Still another object of the invention is to provide a transmission line feed means for first and second antenna arrays mounted in intersecting planes so that each array is excited and so that the resonant frequency of one array may be tuned relative to the resonant frequency of the other array.

Other objects and a fuller understanding of this invention may be had by referring to the following description and claims, taken in conjunction with the accompanying drawing wherein:

Figures 1 is a side view of an antenna array embodying the invention;

Figure 2 is a front view of the antenna array;

2,875,438 Patented Feb. 24, 1959 Figure 3 is a rear view of the array;

Figure 4 is a top view of the antenna array;

Figures 5 through 9 schematically show the progressive changes in the form of the antenna array;

Figure 10 is a radiation pattern obtained from the antennas of Figures 1 to 4;

Figure 11 is a plan view of a modified form of the invention;

Figure 12 is a rear view of the antenna of Figure 11;

Figure 13 is an enlarged view of the cross-over point shown in Figure 11; and

Figure 14 is an enlarged view of the cross-over point of Figure 12.

The Figures 1 to 4 show a complete antenna 20 which is mounted on a horizontal boom 21. The boom may be supported on a vertical mast 22. The boom 21 is approximately one-half Wave length of the working frequency of the antenna.

The antenna 20 comprises generally a first array 23 and a second array 24.

The first array 23 is in a plane which slopes upwardly toward the left, as seen in Figure 2; and the second array 24 is in a plane which slopes upwardly toward the right, as seen in Figure 2. Each array includes a. plurality of elements which generally forms a series of interconnected diamonds. The first array 23 includes first through sixth antenna elements 31 through 36, inclusive.

The second array 24 includes seventh through twelfth elements 37 through 42, inclusive.

Each of the antenna elements 31 through 42 has a first, second, and third portion with the second portion disposed between the first and third portions. All the second portions of the first through twelfth elements 31 through 42 are disposed generally vertically in this embodiment with horizontally polarized antenna elements.

The second portions of the first and second antenna elements 31 and 32 are disposed close to each other and parallel to obtain a current coupling therebetween at a coupling means 45. The second portions of the seventh and eighth antenna elements 37 and 38 are closely spaced and parallel at a coupling means 46 for current coupling. As seen in Figure 4, the coupling means 45 and 46 are relatively close yet have no appreciable mutual coupling, especially since they are disposed on opposite sides of the boom 21.

The third and fourth antenna elements 33 and 34 are similarly current coupled at a coupling means 47, and the ninth and tenth antenna elements 39 and 40 are current coupled at a coupling means 48. The fifth and sixth antenna elements 35 and 36 are current coupled at the coupling means 49, and the eleventh and twelfth antenna elements 41 and 42 are current coupled at the coupling means 50.

The outer ends of the second and third antenna elements 32 and 33 and the outer ends of the fourth and fifth antenna elements 34 and 35 are interconnected at least for effective coupling therebetween to form the series of interconnected diamonds in the first array 23.

Similarly, the outer ends of the eighth and ninth antenna elements 38 and 39 are interconnected and the outer ends of the tenth and eleventh antenna elements 40 and 41 are interconnected to form the series of interconnected diamonds in the second array 24.

The first and seventh antenna elements 31 and 37 are bent forward approximately thirty degrees relative to a plane normal to the boom 21. All other antenna elements are bent backward or forward to approximately the same angle. An exception is the free ends of the sixth and twelfth antenna elements 36 and 42 which are bent rearwardly from the rear end of the boom only about fifteen degrees. The other ends of the sixth and twelfth antenna elements 36 and 42 insulatively support a thirteenth a'ntennaelement 43.

The thirteenth antenna element 43 is cut to a length approximately .47 of a wave length of the working. frequency.

The first'and seventh antenna elements 31 and 37 are cut to a length approximately ,44 o'fa wave length.

The second, third, eighth, and ninth antenna elements 32, 33, 38, and 39 are cut to an overall length approximately .50 of a wave length. The fourth, fifth, tenth, and eleventh antenna elements 34, 35, 40, and 41 are cut to an overall length of approximately .52 of a'wave length. The sixth and twelfth" antenna elements 36 and 42 are cut to an overall length of approximately 1-54 of awavelength. "j

A feeder line 51 is in the order of 'one-halfwave length long and extends from the conjunction of the upper ends of'the tenth and eleventh antenna elements 40 and 41 to the conjunction of the lower ends of the antenna elements 34an'd35. p, H Y Similarly, a'feeder line 52 extends from the conjunction of the upper ends of the antenna elements 34 and 35 to the conjunction of the lower ends of the antenna elements 40 and 41.. Each feeder line 51 and 52 has a central portion 53 and 54, respectively. These central portions lie generally close to the boom 21 but extend below this boom. An impedance matching stub 55 connects'ac'ross the central portions 53 and 54 and a' transmission line may be connected across the matchingstub 55 in conventional manner. The attaching points of the matching stub 55 on the central portions 53 and 54 may be shifted longitudinally, and this will tune the resonant frequency of one array 23 relative to the other array 24. This attaching point may be adjusted to vary the band width.

When'the antenna 20 is used as a receiving antenna, the front of the antenna, which is to the right in Figure 4, will receive the horizontally polarized radiowaves. '.The outer upper end of the first antenna element 31, which is at the lower right of Figure 4, may be considered to be instantaneously positive relative to the outer lower end ofthis element. Simultaneously, the lower outer end of theantenna element 32 will be instantaneously positive relative to the upper outer end of this element 32. This 'means that in the coupling means 45 the currents in both the antenna elements 31 and 32 will be'flowing' in the same direction for current coupling "between these elements. Similarly, in-phase'cu'rrent coupling is achieved at each of the other coupling means.

The coupling means 45 through 50 are actually in- 3 sa of12 artp 4 Figure 5 schematically shows only a portion of the first array '23; namely, the feeder lines 51"and 52'and the antenna elements 34 and 35. This appears similar to a double folded dipole, but cne difference is that in the actual case it was found to have a relatively low impedance rather than a relatively high impedance, which is characteristic of a folded dipole. This elementary antenna of Figure 5 is i taken-as the standard against which the other more complex arrays are compared. This particular configuration obtained a gain which is slightly better than the usual form of straight dipole or folded dipole. For reference purposes this was considered to have a gain of one, namely 0 db.

The Figure 6 s hows schematically, the antenna as it becomes more complex by the addition of the antenna element 36. The measured gain here is 9 db.

The Figure 7 shows the antenna after the addition of I the antenna, element 33. This produced a measured The Figure S shows the antenna after the addition of the antenna elements'31 and 32. This produced a measured gain of 15 db relative to the dipole arrangement of Figure 5. The Figure 8 shows the complete first array The second array 24 was then assembled using antennaelements 37 through 42 to produce the interlinked diamonds. When this second,,array 24 was mounted in place, as shown in Figuresl to 4, and excited only parasitically and not energized from the transmission line, the measured gainwent'upto 18 db., By

exciting both the first and second arrays and by adding the antenna element 43, the measured gain increased to 22 db, This shows that the two arrays coact additively in a given plane, which in this case is illustrated as a horizontal plane, and hence each array may be considered as being disposed nominally in this given plane.

The Figure 10 shows a horizontal pattern of the antenna, Figures 1 to 4, and shows that a high front-toback ratio was obtained as well as a high gain. The

frequency band width of the antenna of Figures 1 to 4 ductive coupling and conductive coupling because the second portions of each of the antenna elements are directly and metallically connected to supports on the boom 21. This is a desirable feature of the present-invention since no insulators are needed at these points. Hence, weather conditions will notalr'ect the performance. The coupling means 45 and the coupling means 46 are spaced sufficiently far apart so that there is'no appreciable interaction therebetween.

This couples all the antenna elements together so that they are all working antenna elements for horizontal polarizationrather than parasitic elements. The fact that the antenna elements taper slightly toward shorter lengths in 'thefront obtains a directive antenna array and the degree of the taper will aife'ct'the band width;

*Thecoupling means 45 to 50 couple together the second portions of eachof the elements 3142, and together with the slightly increasing-overall length of the elements, from front to rear,- provides a means to interfor this particular design was found to be 10 percent of the frequency from one-half power point to one-half power point. This could be increased by increasing the taper of the antenna elements from front-to-back ,or by making one array slightly larger than the other array so that the individual arrays are resonant to different frequency response.

The Figures 11 through 14 show another modification of the invention. The antenna of these figures includes first, second, third, and fourth element supports 61 to 64, inclusive. These have been shownas generally hexagonal in cross-section for this particular design. The first element support 61 carries first, second, third, and fourth elements 71 through 74. The second element support 62 carries fifth through eighth elements 75 through 78. Thefirst, third, fifth, and seventh elements extend forwardly; and the second, fourth, sixth, and eighth elements extend rearwardly. The first, second, third, and fourth elements are arranged parallel to a first plane; and the fifth, sixth, seventh, and eighth elements are arranged parallel to a second plane which intersects the first plane at the center of the element supports 61 through 64. l V The third element support 63 carries ninth, tenth, eleventh, and twelfth elements 79, 80, 81,'and 82. The fourth element support 64 carries thirteenth, fourteenth, fifteenth, and sixteenth elements 83 through 86. A transmission line 65 connects onto the elements 71 and 75 near the element supports 61 and 62. The element supports 61 through 64 provide current coupling between the antenna elements in a manner similar to that afforded by the coupling means 45 to 50in the antenna of Figures 1 to 4. Also, the supports. and62 are physicallycloseyet provide aminimum-v of mutual coupling primarily because of therelativenangle between theiwo. -.;.'Ins.tantaneously,= the. outer. endnoft-element 74. This means that the .cnrrent flowing in the element support 61 between the elements is in phasefor current coupling. Theouter ends ofthe elements 72, 74, 76, and 78 may be connected to the outer ends of elements 79, 81, 83, 811K185 to support the entire array. Alternatively, a boom may be placed between the element supports 62 and 63. I V e As best shown in the enlarged rear view of Figure "14,

the rearwardly extending elements 184 and 86"-a re disposed farther apart on the support 64 than the forwardly extending elements 83 and 85; This effectively increases the length of the rearward elements relative to the forward elements, even without physically ma-kingthe ele ments themselves of different lengths. This same construction is used at each of the supports 61 to 64, and is a means for interconnecting the diamonds formed by the various elements 71 to 86 whereby the forward elements, e. g. 71 and 75, have a shorter overall effective length than the rearward elements, e. g. 72 and -74 An alternative feed arrangement would be to connect the transmission line 65 on the elements '79 and 83 in a position similar to their connection on the elements 71 and 75. r i

Although this invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only byway of example'and that numerous changes in the details of construction and the combination and arrangement of parts may be resorted to without departing from the spirit and the scope of the invention as hereinafter claimed.

What is claimed is:

1. A directional antenna having a front and a rear com prising a center feddipole resonant to a working frequency, a plurality of elements elfectively coupled near the ends thereof to form a plurality of series connected diamonds extending from the front to the rear of said antenna, and means including interconnecting means for said diamonds whereby the forward elements have a shorter overall effective length than the rearward ele ments. it a 2. A directional antenna having a front and a rear comprising a center fed dipole resonant to a working frequency, a plurality of elements effectively coupled at the ends thereof to form a plurality of series connected diamonds extending from the front to the rear of said antenna, and means 'includingmeans for supporting said diamonds whereby the forward side of each set of diamonds has a shorter overall effective length than the rearward side thereof. 3. An antenna having a directivity pattern predominantly toward the front thereof, comprising fiifst'through fourth elements all substantially equal in length, fastening means for said elements having a center, said first and second elements extending forwardly and said third and fourth elements extending rearwardly relative to said fastening means, said third and fourth elements attaching to said fastening means at locations thereon spaced further from said center than the atatching locations of said first and second elements to effectively increase the overall length of saidthird and fourth elements relative to said first and second elements, said first and second elements having opposite polarity, and said first and third elements having the same polarity, said first and third elements attaching to said fastening means on the same side of center, whereby the current flowing between said first andsecond elements and between said third and fourth elements flows in the same direction in said fastening means for in-phase current coupling.

4., An antenna having a directivity pattern predominantly toward the front thereof, comprisingfirst through .fourth elements all; substantially parallel to a first it given plane and substantially equal in length, fastening means for said elements having a center on said first given plane, said :firstand second elements extending forwardly and said third and fourth elements extending rearwardly relative to said fastening means, said third and fourth elements attaching to said fastening means at locations thereon spaced further from said center than the attaching locations of said first and second elements to effectively increase the overall length of said third and fourth elements relative to said first and second elements, said first and second elementshaving opposite polarity and said third and fourth elements having opposite polarity and said first and third elements having the same polarity, said first and third elements attaching to said fastening means on the same side ofsaid first given plane, whereby the current flowing between said first and second elements and between saidthird and fourth elements flows in the same direction. in said fastening means for in-phase current coupling, a second group of fifth jthrough eighth elements substantially similar in length, spacing and position to said first through fourthelements, respectively, the ends of said third and fourth elements being effectively connected to the ends of said fifth and sixth elements.

5. An antenna comprising a first plurality of elements effectively crossing to form an X-shape, first coupling means at said crossing point, said coupling means providing in-phase current coupling between all elements at said crossing point, a second plurality of elements effectively crossing at a second crossing point to form an X-shape, and second coupling means at said second at said crossing point, said coupling means providing in-phase current coupling between all elements at said crossing point, a second plurality of elements arranged generally in a second given plane transverse to and intersecting said first given plane substantially at said crossing point, said second plurality of elements effectively crossing at a second crossing point to form an X-shape, and second coupling means at said second crossing point providing in-phase current coupling between all elements crossing at said second crossing point, said first and second coupling means having a minimum of mutual coupling.

7. An antenna comprising a first plurality of elements arranged generally in a given plane, said elements effectively crossing to form an X-shape, first coupling means at said crossing point, said coupling means providing in-phase current coupling between all elements at said crossing point, a second plurality of elements arranged generally in a second given plane transverse to and intersecting said first given plane substantially at said crossing point, said second plurality of elements effectively crossing at a second crossing point to form an X-shape, second coupling means at said second crossing point providing in-phase current coupling between all elements crossing at said second crossing point, said first and second coupling means having a minimum of mutual coupling, and a transmission line interconnecting the antenna elements in said first and second given planes.

8. An antenna for VHF electromagnetic waves comprising first through fifteenth tubes, inclusive, each said first through twelfth and fourteenth and fifteenth tube having first, second, and third portions along the length thereof disposed in the order named, eachsaid tube being generally of the same length and in the order of onehalf wave length of said electromagnetic wave, a horizontally disposed boom for supporting each of said second portions of said first through twelfth tubes in a substantially vertical position and in first and second generally parallel vertical planes, said first, third, fifth,seventh, ninth, and eleventh of said tubes lying generally in a first acute plane and said second, fourth, sixth, eighth, tenth, and twelfth of said tubes lying generally in a second acute plane, said first and second acute planes intersecting along a line substantially parallel to and close to said boom, said first and second tubes extending forwardly. from a first end of said boom, said third' and fourth tubes extending rearwardly from the first end of said boom, said second portions of said first and third tubes lying closely parallel for mutual inductive coupling therebetween, said second portionsof said second and fourth tubes lying closely parallel for mutual inductive coupling therebetween, the outer ends of said third and fifth tubes being connected together, the outer ends of said fourth and sixth tubes being connected together, the second portions of said fifth and seventh tubes being closely spaced for mutual inductive coupling, the second portions of said sixth and eighth tubes being closely spaced for mutual inductive coupling, the outer ends of said eighth and tenth tubes being connected together and the outer ends of said seventh and ninth tubes being connected together, said second portions of said ninth and eleventh tubes being closely spaced for mutual inductive coupling and the second portions of said tenth and twelfth tubes being closely spaced for mutual inductive coupling, said thirteenth tube being a straight tube carried by the outer end of said first portion of said eleventh tube and the outer end of the first portion of said twelfth tube, said outer end of the third portions of said eleventh and twelfth tubes being left free; said fourteenth tube extending from the junction of the first portion of tubes seven and nine to the junction of the third portions of tubes eight and ten, said fifteenth tube extending from the junction of the third portions of said seventh and ninth tubes to the'junction of the first portions of said eighth and tenth tubes, the second portions of said fourteenth and fifteenth tubes being fairly closely spaced in a horizontal position substantially parallel to said boom, a quarter wave length matching transformer connected to said second portions of said fourteenth and fifteenth tubes, a transmission line connected to said matching transformer, said eleventh and twelfth tubes extending rearwardly from the second end of said boom, said ninth and tenth tubes extending forwardly from the second end of said boom, said fifth and sixth tubes extending forwardly from a position generally at the center of said boom, said seventh and eighth tubes extending rearwardly from said position generally at the center of said boom, first, second, third, and fourth generally diamond-shaped loops formed by four pairs of tubes as viewed in horizontal plan view, said first diamond being formed from tubes three and five, said second diamond being formed by tubes four and six, said third diamond being formed by tubes seven and nine, and said fourth diamond being formed by tubes eight and ten, said boom being approximately half said wave length long, said mutual inductive coupling between said second portions being so phased that the current flowing therein is essentially in phase, said acute planes being approximately twenty degrees from the horizontal on opposite sides thereof.

9. A directional antenna having a front and a rear comprising a radiator resonant to a working frequency, a plurality of elements effectively coupled at the ends thereof to form a plurality of effectively crossed antenna members extending from the front to the rear of said antenna, and means including support means for supporting said members whereby the forward side of each set of members has a shorter overall effective length than the rearward side thereof.

ments, coupling means for said elements having a center,

said first and second elements extending forwardly and said third and fourth elements extending rearwardly rela tive to said coupling means, said elements being connected to said coupling means, with the third and fourth elements effectively having a greater overall length than said first and second elements, said first and second elements having opposite polarity and said third and fourth elements having opposite polarity, and said firstand third elements having the same polarity, and said second and fourth elements having the same polarity, said first and third elements connected to said coupling means 'on the same side of center, whereby the current flowing between said first and second elements and between said third and fourth elements flows in the same direction in said coupling means for in-phase current coupling between said elements.

11. An antenna having a directivity pattern toward the front thereof, comprising first and second interlocked arrays establishing generally first and second planes intersecting along a given line with an acute angle therebetween, each array including first through fourth elements, said first and second elements extending forwardly and said third and fourth elements extending rearwardly .from a point in said given line, a first feed line extending from the outer end of the fourth element in one array to the outer end of the fourth element in the other array and having a central portion near to and generally parallel with said given line, asecond feed line extending from the outer end of the third element in one array to the outer end of the third element in the other array and having a central portionclosely parallel to the other said central portion, and a transmission line'connected across said central portions and movable therealong parallel to said given line to tune the resonant frequency of one array relative to the resonant frequency of the other array.

12. An antenna having a directivity pattern toward the front thereof, comprising first and second interlocked diamond arrays establishing generally first and second planes intersecting along a given line with an angle of approximately forty degrees therebetween, eachdiamond array including first through fourth elements, coupling means for said elements having a center, said first and second elements extending forwardly and said third and fourth elements extending rearwardly relative to said coupling means, said elements being connected to said coupling means with the third and fourth elements effectively having a greater overall length than said first and second elements, said first and second elements having opposite polarity and said third and fourth elements having opposite polarity, and said first and third elements having the same polarity, and said second and fourth elements having the same polarity, said first and third elements connected to said coupling means for in-phase current coupling between said elements, a first feed line extending from the outer end of the fourth element in one array to the outer end of the fourth ele ment in the other array and having. a central portion 'near to and generally parallel with said given line, a

second feed line extending from the outer end of the third element in one array to the outer end of the third element in the other array and having a central portion closely parallel to the other said central portion, and a transmission line connected across said central portions and movable therealong parallel to said given line to tune the resonant frequency of one array in opposite relation to the resonant frequency of the other array.

13. A directional antenna having a front and rear, comprising, a plurality of elements effectively coupled near the ends thereof to form at least one diamond extending from the front to the rear of said antenna and with first and second apexes at the two sides thereof, and transmission line means connected to said diamond to establish said first and second apexes of opposite polarity.

14. A directional antenna having afront and rear,

comprising a plurality of elements effectively coupled near the ends thereof to form at least one diamond eX- tending from the front to the rear of said antenna, and means including interconnecting means for said elements in said diamond whereby the forward elements have a shorter over-all eifective length than the rearward elements.

- 15. An antenna having a front and a rear comprising, first through fourth elements all of generally equal length, fastening means for said elements, said first and second elements extending forwardly and said third and fourth elements extending rearwardly relative to said fastening means, said first and second elements having oppositie polarity, and said first and third elements having the same polarity, whereby the current flowing between said first and second elements and between said third and fourth elements flows in the same direction in said fastening means for in-phase current coupling.

16. An antenna having a front and a rear comprising, first through fourth elements all of generally equal length, fastening means for said elements and having a center, said first and second elements extending forwardly and said third and fourth elements extending rearwardly relative to said fastening means, said first and second elements having opposite polarity, and said first and third elements having the same polarity, said first and third elements attaching to said fastening means on the same side of center, whereby the current flowing between said first and second elements and between said third and fourth elements flows in the same direction in said fastening means for in-phase current coupling.

17. An antenna having a directivity pattern predominantly toward the front thereof, comprising, first through fourth elements all of generally equal length, fastening means for said elements and having a center, said first and second elements extending forwardly and said third and fourth elements extending rearwardly relative to said fastening means, means to effectively increase the overall lengths of said third and fourth elements relative to said first and second elements, said first and second elements having opposite polarity, and said first and third elements having the same polarity, said first and third elements attaching to said fastening means on the same side of center, whereby the current flowing between said first and second elements and between said third and fourth elements flows in the same direction in said fastening means for in-phase current coupling.

18. An antenna comprising, a plurality of elements effectively crossing to form an X-shape and disposed nominally in a given plane, coupling means: at said crossing point disposed transversely to said plane, and said coupling means providing in-phase current coupling be tween all elements at said crossing point.

19. An antenna comprising, a first plurality of elements effectively crossing to form an X-shape and disposed nominally in a given plane, first coupling means at said crossing point disposed transversely to said plane, said coupling means providing in-phase current coupling between all elements at said crossing point, a second plurality of elements effectively crossing at a second crossing point to form an X-shape and disposed nominally in a second plane, second coupling means disposed transversely to said second plane at said second crossing point and providing in-phase current coupling between all elements crossing at said second crossing point,,said first and second coupling means being disposed near the intersection of said two planes.

2-0. An antenna comprising, a first plurality of elements effectively crossing to form a first array, first coupling means at said crossing point, said coupling means providing in-phase current coupling between all elements at said crossing point, a second plurality of elements effectively crossing at a second crossing point to form a second array, and second coupling means at said second crossing point providing in-phase current coupling between all elements crossing at said second crossing point, said first and second coupling means being closely spaced relative to the over-all dimensions of said arrays.

References Cited in the file of this patent Trio Manufacturing Company Advertisement, Radio and Television News, October 1952 edition, page 88. 

